6 Dangerous or Annoying Insects (and Other Pests) in Japan

I definitely don’t want to sound negative. I’m not one of those frustrated people who just keep complaining about Japan, but I want to show you the real Japan in my blog as much as possible.
Aside from all the great and beautiful things I discover during my traveling, there are also some bad things that you should know about before coming or even moving to Japan!

Of course, this is all based on my personal experience and some things I consider to be negative, you might find positive instead.

As it’s summer right now, I think it’s the perfect timing to talk about something that might disturb you quite a bit if you are in Japan during this season of the year!
The crazy heat and humidity coupled with bad insulation of houses is already bad enough for most of us, but that climate causes another problem!
It’s the perfect environment for all sorts of creepy critters and other pests to grow and spread!

First, let’s have a look at the insects: There are many insects that I personally don’t mind or find rather cute, especially those that are similar to the ones I’m used to from back home.
Actually there are even some really beautiful insects as well, such as butterflies or the red dragonfly. The grasshopper in the photo above is rather cute, too!

However, the majority of them is disgusting. And not only that!
The main reason why I wrote this blog post is to warn you! Some of them are dangerous and many tourists don’t even know about it! Some can hurt you badly, others can kill you!
Although chances are low that it will happen to you, I think it’s important you have at least a rough idea of what to expect.

1. Suzumebachi – The Killer Hornet:

Suzumebachi (スズメバチ、雀蜂、胡蜂) which consists of the words “suzume” (sparrow) and “hachi” (bee, hornet) is better known in Western countries as Japanese giant hornet (Vespa mandarinia japonica).
THIS is my personal nightmare! Of course I’m afraid of a few insects and animals, but only bees, wasps and hornets cause me to panic!
And I’m talking about the relatively tiny European ones!
Now, this one is HUGE! And not only that, it can kill you! I’m not kidding! I wish I was!
Obviously somebody who is allergic to the venom of bees will die from it. Their venom is just so much stronger which is why it also can kill people who aren’t allergic to them, even adults, if the dose is sufficient! A significant number of people die every year in Japan because of this little monster!

My Japanese co-workers keep telling me that one sting doesn’t kill you, but the second time will, because by that time your body will show an allergic reaction. I’m not sure if that’s really true, but Japanese people keep telling me that.

Here’s a video where you can see a suzumebachi from close up. It’s really a huge monster!(Note: It’s already dead, otherwise it would be too dangerous and stupid to do what that guy did!)

As most insects it’s active in summer, but you’re most likely to run into it in September and October. That’s also when I found one sitting on my bedsheets that I had out for airing last year in October. (Please excuse the horrible quality of the photo, but I’m sure you understand that I didn’t want to go any closer.)

If you get stung, wash the wound with clear water, then try to get the poison out by squeezing. Don’t suck it out!
You should use a cream that contains “histamine”. After these frist-aid steps, go to a hospital or – if in the mountains – to a nearby mountain hut and get an antidote!

Those hornets can be very aggressive. Avoid wearing black clothes. If you have a dark hair color, then wear a bright-colored cap. Don’t use perfume!

This is probably a so-called “black suzumebachi” (クロスズメバチ), but I’m not sure. It’s always better to assume you’re facing something dangerous than the other way round, right?

There are many similar bee-like insects and all of them are huge! Even horseflies look similar if they’re just passing by. My strategy is to just run away instead of confirming what it is! That’s also the only strategy that kept me from being stung. Staying calm didn’t help!

While it’s not very common that they invade your house (unless you live next to trees or they decided to have their nest under your roof), they’re still very present especially in rural areas of Japan. When traveling, be careful!

If there are a lot of them around, you’ll find signs like this.
They suggest that you don’t make any hectic moves and slowly get some distance between you and the hornet.“If you stay calm, they are not scary insects at all!!” – Yeah, right .. not gonna stay around to test if that’s true or not!
The photo was taken in Yumebutai on Awaji Island, Kobe.

2. Mukade – Centipede

You’ll find a huge variety of centipedes in Japan, but one of them is especially dangerous:
Mukade (ムカデ、百足) is another giant creature in Japan, yet correctly spoken it’s not an insect.
In summer, especially after rainy season you might find them in your house or in your bed.
You are most likely to see them if you live in the countryside close to mountains. They are very territorial, so just kicking them out, won’t help.
They would come back. I heard that many people pour boiling water on them and then cut them into half.

The following video has a lot of interesting information about the mukade:

The problem with this critter is that it’s very aggressive and it can bite you.
People often describe the pain as 10 times stronger than that of a common bee sting. Also the swelling on your skin can be quite bad.
In summer it’s very common for them to be all around the place outside, especially at night. I just had a very unpleasant experience in Kyoto a few days ago which I posted on Facebook.

There are a lot of other types of centipedes as well. This photo was taken in Gifu (next to Gifu Castle) in August 2010.

You don’t have to go to a hospital if you were bitten by a mukade, but it will hurt a lot, so it’s good to know what to do.
Go to a drug store and get something like “ムヒアルファEX“. It will help to cool the skin and release the pain a little.
Unfortunately there’s not much you can do to prevent them from invading your apartment. Japanese people tend to use this powder that is spread around the house, but it can’t guarantee that they will stay away!

3. Huntsman Spider:

You can take a deep breath now. This fellow is not dangerous, but it might freak you out nevertheless.
I’m not afraid of spiders, but when I saw my first huntsman spider I freaked out!
Their legspan can reach up to 30cm!
Actually those spiders are not native to Japan, but have been accidentally imported!
They do not have webs, but hunt their prey, often by jumping on it from above. They’re also very fast! That’s why they’re called “huntsman”.

The one in the photo was sitting on the wall outside of my apartment and even had an egg sac below its body!
A female spider can get aggressive when somebody tries to attack their eggs. Usually they are harmless, but bite if you provoke them.
The venom is not harmful to a healthy adult and usually there’s no need to go to a hospital after being bitten.

You’ll most likely run into them during rainy season as they look for shelter.
As scary as this spider might look, it’s actually useful because it eats cockroaches … probably the NUMBER 1 PEST in summer!

4. Cockroaches:

If you’re going to live in Japan you need to know that you will have issues with these disgusting little guys! They are everywhere in summer. It doesn’t matter how clean or new your apartment is, they will come and pay you a visit!
Don’t freak out! If you see one in your apartment, get rid of it. It doesn’t necessarily mean you have a nest or anything.
As this is such a huge issue in Japan, you can easily buy traps and poison for cheap in most supermarkets and drug stores.
Very common are the “Hoi Hoi sticky traps” and the poisonous traps. A normal insect spray often doesn’t work well, so the “Goki Jetto spray” is the way to go.

I’m sorry I don’t have a photo of a cockroach although this is the critter I run into the most!
Actually we have one at work almost every day. As they are so fast, you’re too busy getting rid of them that you won’t have time to take a photo, but I’m sure most of you know how they look.

In Germany you’ll only see roaches in very dirty places, so I was so shocked when I saw my first cockroach here in Japan. As I never had seen one before I wasn’t even sure if it was one at first!

5. Cicadas:

When thinking about insects in Japan, cicadas were always the first to come to my mind.
If you watch an anime that takes place in summer, you’ll surely always hear a buzzing sound in the background.
When I was younger I thought that was some kind of machine, but it’s actually the cicadas!

Cicadas are quite big and some find them disgusting. I’m not a big fan of them, but I also don’t mind them.
Most of the time their buzzing is considered as a natural noise in summer and people find it relaxing to hear, but in some parts (e.g. parks) they can get so loud that it really hurts your ears! We’re talking about up to 120 dB! Technically that’s loud enough to cause permanent hearing loss in humans!

Other than the noise they are usually totally harmless for humans!

6. Other Pests:

The following animals and insects aren’t necessarily something you will run into when in Japan. It greatly depends on where you live and most tourists won’t even know they exist here. Yet I thought it was interesting to mention and for people who intend to move to the Japanese countryside it might be very interesting information.

6.1. Frogs:

If you live in the Japanese countryside right next to rice fields, then from about May to August you’ll suddenly have extremely loud, croaking neighbors. The frogs are harmless and are actually a sign that the rice fields are in good condition.

The most common one is the so-called “amagaeru” (アマガエル, Japanese tree frog). It’s very tiny and I find them actually quite cute.
During the daytime they stay in the rice paddies, but at night they become active, hop near lights to catch the insects there.
That’s why I find some of them around my front door when I come home from work at night.
They’re actually quite useful and not a pest – apart from their noisy croaking at night.

6.2. Geckos:

To me personally geckos are not a pest at all. They are usually outside my windows at night to catch all the insects.
I find them rather cute and wouldn’t freak out if one of them comes into my apartment.

However, some of you might find them disgusting and you have to know that they are VERY common in summer, especially in the countryside.
I see them every night!

6.3. Mice:

Personally I have no experience with mice. I found a dead mouse in one of my cockroach(!) traps in late November!
They’re invading houses or apartments every now and then.
It’s especially likely to happen in the countryside and in old Japanese houses.
When you go into a drug store or a supermarket, you’ll find a lot of mice traps. That alone shows that it’s quite an issue in Japan.
Did you ever have issues with mice?

6.4. Poisonous snake, Habu:

Japan doesn’t have that many poisonous animals. One of the most dangerous (as in: causing a lot of deaths per year) is the earlier mentioned “suzumebachi”.
Another really dangerous one is a poisonous snake called “Habu” (波布, Trimeresurus flavoviridis).
As far as I know they can mainly be found in Okinawa and it’s very unlikely that you’ll run into one.
While the venom is extremely strong, fatality rate is only 3%. If you are bitten, get medical treatment immediately.
In most cases you won’t die from the poison, but permanent disability can be caused in some cases.

6.5. Bats:

What? Bats? Well, to be honest this is more like a personal story, but I thought it might be good to share it nevertheless. I doubt that anybody will EVER run into the same problem, though.
Yes, Japan has bats – like many other countries, including my home country!
Moving to a really rural area, I suddenly had many of them around. I didn’t mind.
Until the first somehow made it into my apartment. I got the shock of my life! It was flapping around in panic, dropping poo all over the place.
As bats are an endangered species, we are not allowed to kill them. Not that I wanted to. It was rather cute, but annoying.
I opened the windows and waved my arms until it finally found its way out.
At first I thought it was a coincidence, but a few days later I had the next bat in.
After many sleepless nights and a lot of bat poo, I finally found out that they came in through the kitchen hood.
When I opened it, lots of poo fell out. After cleaning it thoroughly I literally had a mountain of poo in there. So disgusting.
A metal grid outside (outer kitchen hood) finally solved the problem. Now, I only find some bat poo on my car sometimes.
Bats sometimes live in attics of old Japanese houses, but they’ll find other places to stay like in my case.
I think it’s important to know about that, although it really doesn’t seem to be very common.
Usually they are very shy, but they CAN bite and they COULD have rabies, so be careful!

As you can see, being in Japan in summer can be a quite disgusting experience.
There are so many huge insects, but also many tiny flies and mosquitos. You’ll have mountains of dead insects in front of your door the next morning!

Especially for Japanese boys this is paradise, though. They buy huge nets to go insect hunting.
They’re particularly interested in all the big beetles. Japan has indeed a lot of them. There are also many insect museums all around Japan.
If you ever happen to visit Nagoya Castle, there is a nice exhibition of all sorts of insects in one of the floors:

I hope this blog post didn’t freak you out too much, but it is a fact that all these creepy critters are around and you should know about them.
I think it’s important to know which ones are dangerous and what to do when you encounter them – or how to get rid of them.
I couldn’t cover the topic in depth, but I hope I was able to give you a good overview.
And if you are actually fascinated by insects in Japan and want to see and read more about it, I can recommend this blog to you.

There are so many creepy things out there, so let me know if you’ve ever run into something I didn’t mention here.
Please share your horror stories with us!
Were you ever bitten by a mukade or stung by a suzumebachi?

Related Posts:

I am familiar with some of those insects. We don’t have the giant hornet, but plenty of other noxious stinging ones, and I run away from them, being allergic to their sting. I have actually been literally attacked by a wasp 3 times. Not a pleasant experience. Not to speak of the times some bee got caught in my clothing and stung me.

I can testify to the loudness of those tiny tree frogs, very surprising when large frogs have instead a rather harmonious low call.

We have some dangerous spiders, including the black widow, whose bite is very bad. Cockroaches, including huge ones in the south, grasshoppers, crickets [whose sound at night can be ear splitting]. In our area we have regular cicadas, 7-year cicadas, and 17-year cicadas. Those last 2 come back after 7 or 17 years, in large numbers. The last 2 times we had the 17 year ones, their noise was incredible, and the smell awful as they died in droves all over the place after laying their eggs.

Geckos are cute and very useful. Mice and rats…every supermarket, hardware store, etc. in the US has traps! My cats brought me regular hunting trophies…

Bats, we have twice had one trapped in the house, and it was hard to get rid of them. I know they are useful, but I really dislike for them. Ugly creatures!

Woah! I guess I’m spoiled coming from Germany. We don’t really have that many scary insects.
We apparently have the huntsman spider, too, but I’ve never ever seen it.
There are roaches, but only in REALLY dirty places, so the first time I ever saw one was in Japan!
We do have small, very aggressive wasps in summer. They are EVERYWHERE!
You cannot sit down and enjoy a parfait or whatever, cuz they attack immediately. It’s freaking me out!
At least they are not dangerous! :hum:

Oh, you don’t like bats?
Actually, when the first one came in I thought it was rather cute.
I still like them, I just hated the fact that they invaded my apartment and dropped their excrements everywhere! :mukatsuku:

In my long comment I forgot to mention one pest you should be glad isn’t in Japan [or Europe}: fire ants. There are dangerous tiny little things. They live in big colonies, making ant hills any old place. They love establishing nests in flower pots. You lift the pot, and all of a sudden your hands and arms have dosens of ants running on them and biting!

Their bit is painful, itchy, and quickly gets infected because of the venom. They are very common throughout the southern US. On top of it they are hard to get rid of.

Japan is pretty good compared to my home country of Australia. We have some of the most deadly snakes and spiders in the world. Living near the mountains in Japan, the worst that I’ve seen has been small mountain snakes and huntsman spiders :)

You haven’t lived in the country enough in Japan! The insect in Australia might be more deadly however Japans are horrible!
Winter you have stink bugs EVERYWHERE! And now its summer theres the Giant hornets, huge mosquitoes, mites, crickets and Omg the list goes on. Japans mozzies and mites bites are lot bigger and ichier as well! I actually am starting to miss Aussies bugs!

I definitely agree with you that Japan has an impressively wide array of terrible insects. And they’re all HUGE. It’s like everything else in this country is tiny, except for the bugs. That is not a good situation. The spiders are freaking terrifying too–they’re like the size of a small cat.

Wow! When I was reading your tweets & LJ entries I thought your insect problem was a horrible experience :( but I didn’t really register just how horrible it is. Now seeing the photos, I TOTALLY GET IT NOW!~’ nothing like a good visual knowledge noh?!
( T_T)人(T_T ) *pats back* Hang in there!~

Yes, it was quite bad and on top of that my landlord didn’t believe me at first.
(Of course I make up stories about bats that are invading my apartment .. WTF?!)
Thanks, it’s resolved now, but it surely was a freaky time!

The only “problem” I ever had was with cockroaches in an apartment I rented for a week in Tokyo (they were under the tatami mats, my boyfriend freaked out, later he told me that he had seen plenty in the kitchen and the bath and didn’t want to tell me). I also saw some in the ground floor dormitory that I stayed in for two weeks. What surprised me is how HUGE they are compared to what I know from Austria. HUGE! And they FLY!

I also saw my one and only Habu snake on Yakushima. Luckily (?) it was dead. At first I thought that I had killed it accidentally, so I stopped my car right away and went back. The blood was already dry though. I took some pictures to be check later and it actually was a Habu snake. I didn’t really know they had them on Yakushima, but they’re pretty much everywhere South of Kagoshima.

Ewww ….. I heard they’re quite common in guest houses especially, but they’re really EVERYWHERE anyways!
If you come ot Japan in summer and stay for a while and DON’T see any roaches anywhere then you’re really lucky, I guess.

Wow, glad it was already dead! Didn’t know they exist in Yakushima, too!
Good thing I didn’t know when I went there! *g*

I wouldn’t know much about that as I rarely explore the ocean. I think that’s more your field, isn’t it? ;P

I always love your posts. they’re very detailed and the photography is AWESOME! But omg I’m scared of bugs…yes, I’m one of those girls. HAHA. But i do find some bugs pretty but most of them . . . no. And totally remember how much the cicadas made noises in the neighborhood -_-;;

Gawd, I’m sure you’d love it in Japan then!
Seriously our insects in Germany are babies compared to the ones here in Japan!
I find something creepy in my apartment almost every day!
I don’t kill all of them, only the ones that could harm me. :(
2 nights ago there was a cute little gecko. I just put a cup on it, to capture it and kick it out.
I find them rather cute and there’s no reason to kill them, but they would die if they stayed in my apartment.

I was away for 2 weeks (summer vacation trip) and when I came back I had tiny spider webs in almost every single corner of my apartment.
I’m pretty sure all sorts of insects held a party while I was gone! :hum:

Yikes! If I didn’t already live in Japan I might be scared. I live in west Tokyo – never seen a cockroach (only poo and one egg sack at my work), hornet, gecko, frog, mukade, or huntsman. Of course cicadas are classic (though I find the nymph shells rather disgusting), it’s only the tiny ants I’ve had a problem with in the apartment (rainy season), but as soon as you clean those places you never clean (behind the desk, etc.) and get some tasty poisonous pellets for them to eat, it’s fine. Kind of unnerving though if you sleep on the floor.. living above the first floor probably helps with pests. My first apartment was on the 10th floor, maybe there was a mosquito or some gnats a couple times. Have yet to thoroughly experience the countryside. Nice post!

Hi nic!
You were extremely lucky then! Roaches are everywhere, also in big cities like Tokyo.
A lot of people I know who have lived in Tokyo for a long time had roaches around.
It also doesn’t matter if you live in a higher floor, so I guess 10th floor is a different story after all! ;P

I had goosebumps while reading this! And I had to scroll past the spider photo, I can’t stand them. Especially when the’re 30 cm!! :huh: But it was really informative. My friend who lives in Kyoto actually said that he was playing with a Suzumebachi in class, without knowing that it was dangerous! He told me that the teachers panicked when they found out… I have a really stupid friend. :C

OMG!! See? That’s one reason why I wanted to write this post!
So many people don’t seem to know which ones are really dangerous!
Of course, Japan has not any super dangerous insects like some other countries, but it’s still good to know which ones you better shouldn’t touch (or play around with :hum: ).

I get quite a few mukade, or centipedes, around my apartment, which is both ancient and near the forest in Kyoto. In the old days many people didn’t have bathrooms in their houses. They used public baths, or sento, which were everywhere. My apartment is so old that the shower/bath was added on, and is off my balcony! I leave the door open all the time to discourage mould (another yucky problem of hot humid climates!) Unfortunately bugs always find their way in, so I have to check before using it. Twice I haven’t checked carefully enough, and have found a centipede crawling up my leg. Very scary, but at least someone had told me what to do in that situation… if you try to brush it off face first, of course you will be bitten. You must brush it off from behind, in the direction it is crawling. Both times, I escaped being bitten by following this tip. The second time it was a pretty big centipede, so I was really glad it didn’t bite me!

We had a suzumebachi at my workplace yesterday. It was a horrible moment!
I’m so afraid of them! :( …

Actually I would have brushed it off from the top (from its mouth). If you touch its back, wouldn’t it notice something is wrong and bite?
Well, probably I’d just completely freak out if one crawls up my leg and would just run around hysterically until I get bitten. (T__T) …

Really interesting! I love the pictures. Well, i just want to say while living in Germany are the ticks (Zecken). it is not because they are ugly or whatever But because the horrible stories people told me about the illnesses after…I never saw one. Just don’t feel like laying on the grass in Summer.

Oh, yes! I totally agree! Ticks are absolutely horrible. My cats used to have them a lot, but even my grandma had been bitten by one once. Luckily she went to the doctor right away, but often you don’t notice and that’s when all kinds of evil diseases can break out much later! :(

About Zooming Japan

This Japan blog is run by Jasmine T. Blossom - a German who's lived in Japan for over 7 years.

She has travelled to all 47 Japanese prefectures and over 100 Japanese castles, experienced natural disasters, cultural oddities and work life in Japan. She loves exploring things off the beaten path, so you'll find a lot of great travel inspiration here.

In this blog Jasmine offers a close-up view of all the good and bad that comes with living and traveling in Japan. Hire her as a Japan expert.